Cromolyn derivatives and related methods of imaging and treatment

ABSTRACT

Novel cromolyn analogs useful as imaging agents for detecting atherosclerotic plaques and for treating atherosclerosis and Alzheimer&#39;s Disease, and methods of making the cromolyn analogs, are disclosed. The cromolyn analogs have the general formula (I), or formula (II); wherein X is OH, C1-C6 alkoxyl, 18F, or 19F; Y and Z are independently selected from a C1-C6 alkyl, CpC6 alkoxyl, halogen, un-substituted or C1-C6 substituted amine, 18F, 19F, or H; and n is 1, 2, or 3; and wherein for structure (I), if n are both 1 and Y and Z are both H, X is not OH.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application represents the U.S. national phase application of PCTInternational Application No. PCT/US2010/022495 filed on Jan. 29, 2010,which claims priority to U.S. Provisional Application No. 61/148,245filed on Jan. 29, 2009, both of which are fully incorporated byreferenced herein.

This application claims the benefit of U.S. Provisional application61/148,245, filed Jan. 29, 2009, which is incorporated herein byreference in its entirety.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable.

FIELD OF THE INVENTION

The invention relates generally to medical imaging and diseasetreatment. In particular, the invention is directed to cromolynderivatives for use in positron emission tomography (PET) imaging andrelated methods of diagnosis and therapeutic treatment.

BACKGROUND OF THE INVENTION

Coronary artery disease is the leading cause of morbidity and mortalityin the United States and in most developed countries. Atherosclerosisand its complications such as myocardial infarction and stroke, ismainly responsible for coronary artery disease. All together,atherosclerosis accounts for at least forty-three percent of all deathin the United States affecting over 60 million people (1).

Advances in basic science indicate coronary artery disease is aninflammatory process, characterized by a long cycle of irritation,injury, healing and re-injury to artery endothelial cells. There isgrowing evidence that mast cells are found in the various stages ofatherosclerosis, coronary inflammation and cardiac ischemia (2-7). Mastcells, located in connective tissue, play an important role in helpingthe immune system defend tissues from disease by activating the releaseof intracellular mediators (degranulation), as well as attracting otherkey players of the immune defense system to areas of the body where theyare needed. In response to vascular injury, cardiac mast cells interactwith lipoproteins to deliver lipids to macrophages, and to release alarge variety of cytokines that affect smooth muscle cells and Tlymphocytes. This process can develop into the more advanced and complexocclusive lesions, termed fibrous plaques. Other pro-inflammatorymediators released by mast cells are histamine, which can constrict thecoronaries, and cytokines IL-6 and IFN-gamma, which induce degradationof the extracellular matrix and the death of smooth muscle cells in thewall of the aorta, weakening the walls and allowing it to dilate. Thus,the inflammatory response stimulates endothelial dysfunction causingmigration and proliferation of smooth muscle cells that becomeintermixed in the area of inflammation to form fibrous plaques andcomplicated lesions.

Disodium cromoglicate, termed “cromolyn,” is the disodium salt ofcromoglicic acid. It is used as an anti-inflammatory medication.Cromolyn is described in the literature as a mast cell stabilizer sinceit works by preventing the release of mediators such as the vasoactiveand pro-arrhythmogenic chemical histamine and cytokines from mast cellsthus stabilizing inflammatory cells. Prevention of mediator release isthought to result from indirect blockade of the entry of calcium ionsinto the membrane of sensitized mast cells. Cromolyn has also been shownto inhibit the movement of other inflammatory cells such as neutrophils,eosinophils, and monocytes (8).

Recent studies in mice have demonstrated that systemic mast cellactivation during atherogenesis leads to plaque formation (9).Furthermore, treatment of the animals with the mast cell stabilizercromolyn prevented dinitropphenyl-albumin-induced plaque expansion. Inanother study, cardiac mast cell activation was studied in mice afterstress-related coronary inflammation (10). Activated mast cells werefound adjacent to atherosclerotic vessels. In cromolyn treated mice,release of the pro-inflammatory cytokine interleukin-6 (IL-6) present inmast cells, was partially inhibited.

There is growing evidence that activated cardiac mast cells areincreased in association with coronary inflammation, myocardialinfarction, as well as ischemic cardiomyopathy. Moreover, mast cells canpromote the formation of human atherosclerotic lesions by causingendothelial dysfunction of the heart's arteries that lead to plaquebuildup. Since cromolyn targets sensitize mast cells, a labeled cromolynanalog potentially could serve as a diagnostic probe for early detectionof coronary artery disease.

As can be appreciated, it would be desirable to obtain new imagingagents useful for detecting degenerative diseases in human subjects. Inparticular, novel imaging probes that associate with markers ofinflammation such as mast cells would facilitate the early detection ofinflammatory diseases such as atherosclerosis by utilizing sensitive andnon-invasive approaches such as PET or MRI imaging. Such new compoundsmay also provide unexpected therapeutic benefits for treatment ofconditions including, but not limited to, inflammation, infection,atherosclerosis and Alzheimer's Disease

SUMMARY OF THE INVENTION

The inventors show herein the synthesis and use of new cromolynderivatives. Accordingly, the invention provides imaging agents suitablefor imaging sites of inflammatory activity, including atheroscleroticplaques in the heart, brain and carotid artery, and β-amyloid plaques inthe brain. In addition, the invention provides compounds that providetherapeutic effects in the treatment of various conditions including,but not limited to, inflammation, infection, atherosclerotic plaque, andAlzheimer's Disease.

In a first aspect, the invention provides a compound having the formula:

-   or an ester or salt of (I) or (II);-   wherein: X is OH, C₁-C₆ alkoxyl, ¹⁸F, or ¹⁹F; Y and Z are    independently selected from a C₁-C₆ alkyl, C₁-C₆ alkoxyl, halogen,    un-substituted or C₁-C₆ substituted amine, ¹⁸F, ¹⁹F, or H; and n is    1, 2, or 3; and wherein for structure (I), if n are both 1 and Y and    Z are both H, X is not OH.

In certain embodiments, X is ¹⁸F or ¹⁹F and, more preferably, Y and Zare hydrogen. A particularly preferred compound has the structure:

or is a salt or ester thereof.

In another embodiment, at least one of Y and Z is ¹⁸F or ¹⁹F and, morepreferably, X is OH. Particularly preferred compounds have thestructures:

or are corresponding salts or esters thereof.

In an alternative embodiment, the compound lacks a radiolabel and,preferably, X is OH and Y and Z are hydrogen, except that in such anembodiment comprising structure (I) wherein X is OH and Y and Z arehydrogen, both n cannot be 1.

Preferred compounds of the invention, particularly for imaging purposes,localize to atherosclerotic plaques in the heart, brain and/or carotidartery of a subject, or to β-amyloid plaques in the brain of a subject.

In another aspect, the compounds of the invention are provided in theform of a pharmaceutically appropriate dosage of one or more of thecompounds described and claimed herein formulated with apharmaceutically acceptable carrier.

As can be appreciated, the compounds of the invention are useful forimaging in other modalities in addition to PET imaging. Exemplarycompounds may be optionally isotopically labeled with isotopes such asthe ¹⁹F isotope, or ¹³C isotope to facilitate nuclear magnetic resonanceimaging (MRI).

In yet another aspect of the invention, a method for providing apositron emission tomography (PET) scan of a subject is provided. Such amethod includes steps of: (a) administering to a subject a compoundcontaining an ¹⁸F label as described and claimed herein; and (b) imaginggamma rays emitted due to the compound within the subject in order toprovide a PET scan of the compound contained in the subject.

In preferred methods, the presence, absence or level of the compoundwithin the subject is indicative of a disease state including, but notlimited to, atherosclerotic plaque alternatively present in the heart,brain, or carotid artery of the subject.

The subject is preferably a living animal, most preferably a human.

The compound is typically administered to the subject via intravenous(IV) injection.

In certain alternative methods, an additional step of contrast imagingthe subject by magnetic resonance imaging (MRI) or x-ray computedtomography (CT) is included.

In yet another embodiment, the invention provides a method for providinga magnetic resonance image of a subject. Such a method includes stepsof: (a) administering to a subject a compound containing an ¹⁸F labelaccording to the present invention; and (b) imaging the subject in orderto obtain a magnetic resonance image of the compound contained withinthe subject.

The presence, absence or level of the compound within the subject isindicative of a disease state, preferably atherosclerotic plaque presentin the heart, brain, or carotid artery of the subject.

The invention further encompasses treatment methods, including treatmentof atherosclerotic plaque in a subject. Such a method includes steps ofadministering to a subject an effective dosage of a compound of theinvention, whereby the atherosclerotic plaque is treated in the subject.

In an alternative method, the invention provides a method of treatingAlzheimer's Disease in a subject including the steps of administering toa subject an effective dosage of an inventive compound, wherebyAlzheimer's Disease is treated in the subject.

Also provided by the invention are novel methods of efficientlypreparing fluorinated compounds. Such methods provide for quickersynthesis and purification than is seen in conventional methods.Accordingly, the methods are particularly suited for fluorinatingcompounds with radiolabeled fluorine for use in imaging applications.

In some embodiments of a method of preparation, a fluoride moiety iscontacted with an organic compound having a triflate or tosylate moietyon an aliphatic carbon atom under anhydrous or aprotic conditions. Undersuch conditions, the fluoride moiety acts as a nucleophile and thetriflate or tosylate acts as a leaving group in a nucleophilicsubstitution reaction, resulting in the fluorination of the organiccompound. Preferably, the fluoride moiety used in the method is F-18.

In certain such embodiments, the organic compound contacted with thefluoride moiety is1,3-bis[(tolylsulfonyl)oxy]-2-[(trifluoromethyl)sulfonyl]oxy-propane,and the resulting product is further reacted with other compounds toprovide a fluorinated cromolyn derivative. In one embodiment, cromolynderivatives are provided wherein X in structure (I) or structure (II)above is a fluorine atom. Preferably, the fluorine atom is radiolabeledF-18.

In yet other embodiments of a method of preparation, a fluoride moietyis contacted under anhydrous or aprotic conditions with an organiccompound having an activated aromatic ring wherein the aromatic ring islinked to a nitro group, a substituted ammonium ion, a substitutedsulphonium ion, a substituted phosphonium ion, or a halogen. Under suchconditions, the fluoride moiety exchanges for the nitro group,substituted ammonium ion, substituted sulphonium ion, substitutedphosphonium ion, or halogen, resulting in the fluorination of theorganic compound on the aromatic ring. Preferably, the fluoride moietyused in the method is F-18.

In certain such embodiments, the organic compound contacted with thefluoride moiety is a cromolyn derivative-based substituted ammonium saltwherein the nitrogen atom of the substituted ammonium ion is attached toan aromatic ring of the chromolyn derivative. In some such embodiments,cromolyn derivatives are provided wherein Y or Z in structure (I) orstructure (II) above is a fluorine atom. Preferably, the fluorine atomis radiolabeled F-18.

Of course, the invention also contemplates the use of a compound asdescribed and claimed herein for the manufacture of an injectable dosagefor the in vivo imaging of a subject as well as a medicament for thetreatment of disease conditions such as atherosclerotic plaque andAlzheimer's Disease. In addition, the invention encompasses the use ofthe present compounds in in vivo imaging of a subject and treatment ofdisease conditions.

Other objects, features and advantages of the present invention willbecome apparent after review of the specification, claims and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates the biodistribution of cromolyn Compound A followingintravenous injection in mice.

DETAILED DESCRIPTION OF THE INVENTION

I. In General

Before the present materials and methods are described, it is understoodthat this invention is not limited to the particular methodology,protocols, materials, and reagents described, as these may vary. It isalso to be understood that the terminology used herein is for thepurpose of describing particular embodiments only, and is not intendedto limit the scope of the present invention which will be limited onlyby any later-filed nonprovisional applications.

It must be noted that as used herein and in the appended claims, thesingular forms “a”, “an”, and “the” include plural reference unless thecontext clearly dictates otherwise. As well, the terms “a” (or “an”),“one or more” and “at least one” can be used interchangeably herein. Theterms “comprising” and variations thereof do not have a limiting meaningwhere these terms appear in the description and claims. Accordingly, theterms “comprising”, “including”, and “having” can be usedinterchangeably.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meanings as commonly understood by one of ordinary skillin the art to which this invention belongs. Although any methods andmaterials similar or equivalent to those described herein can be used inthe practice or testing of the present invention, the preferred methodsand materials are now described. All publications and patentsspecifically mentioned herein are incorporated by reference for allpurposes including describing and disclosing the chemicals, instruments,statistical analysis and methodologies which are reported in thepublications which might be used in connection with the invention. Allreferences cited in this specification are to be taken as indicative ofthe level of skill in the art. Nothing herein is to be construed as anadmission that the invention is not entitled to antedate such disclosureby virtue of prior invention.

The terminology as set forth herein is for description of theembodiments only and should not be construed as limiting of theinvention as a whole. Unless otherwise specified, “a,” “an,” “the,” and“at least one” are used interchangeably and mean one or more than one.

As used herein, the term “organic group” is used for the purpose of thisinvention to mean a hydrocarbon group that is classified as an aliphaticgroup, cyclic group, or combination of aliphatic and cyclic groups(e.g., alkaryl and aralkyl groups). In the context of the presentinvention, suitable organic groups for cromolyn derivatives of thisinvention are those that do not interfere with the cromolyn derivativesimaging activity. In the context of the present invention, the term“aliphatic group” means a saturated or unsaturated linear or branchedhydrocarbon group. This term is used to encompass alkyl, alkenyl, andalkynyl groups, for example.

As used herein, the terms “alkyl”, “alkenyl”, and the prefix “alk-” areinclusive of straight chain groups and branched chain groups and cyclicgroups, e.g., cycloalkyl and cycloalkenyl. Unless otherwise specified,these groups contain from 1 to 20 carbon atoms, with alkenyl groupscontaining from 2 to 20 carbon atoms. In some embodiments, these groupshave a total of at most 10 carbon atoms, at most 8 carbon atoms, at most6 carbon atoms, or at most 4 carbon atoms. Cyclic groups can bemonocyclic or polycyclic and preferably have from 3 to 10 ring carbonatoms. Exemplary cyclic groups include cyclopropyl, cyclopropylmethyl,cyclopentyl, cyclohexyl, adamantyl, and substituted and unsubstitutedbornyl, norbornyl, and norbornenyl.

The term “heterocyclic” includes cycloalkyl or cycloalkenyl non-aromaticrings or ring systems that contain at least one ring heteroatom (e.g.,O, S, N).

Unless otherwise specified, “alkylene” and “alkenylene” are the divalentforms of the “alkyl” and “alkenyl” groups defined above. The terms,“alkylenyl” and “alkenylenyl” are used when “alkylene” and “alkenylene”,respectively, are substituted. For example, an arylalkylenyl groupcomprises an alkylene moiety to which an aryl group is attached.

The term “haloalkyl” is inclusive of groups that are substituted by oneor more halogen atoms, including perfluorinated groups. This is alsotrue of other groups that include the prefix “halo-”. Examples ofsuitable haloalkyl groups are difluoromethyl, trifluoromethyl, and thelike. “Halogens” are elements including chlorine, bromine, fluorine, andiodine.

The term “aryl” as used herein includes monocyclic or polycyclicaromatic hydrocarbons or ring systems. Examples of aryl groups includephenyl, naphthyl, biphenyl, fluorenyl and indenyl. Aryl groups may besubstituted or unsubstituted. Aryl groups include aromatic annulenes,fused aryl groups, and heteroaryl groups. Aryl groups are also referredto herein as aryl rings.

Unless otherwise indicated, the term “heteroatom” refers to the atoms O,S, or N.

The term “heteroaryl” includes aromatic rings or ring systems thatcontain at least one ring heteroatom (e.g., O, S, N). In someembodiments, the term “heteroaryl” includes a ring or ring system thatcontains 2 to 12 carbon atoms, 1 to 3 rings, 1 to 4 heteroatoms, and O,S, and/or N as the heteroatoms. Suitable heteroaryl groups includefuryl, thienyl, pyridyl, quinolinyl, isoquinolinyl, indolyl, isoindolyl,triazolyl, pyrrolyl, tetrazolyl, imidazolyl, pyrazolyl, oxazolyl,thiazolyl, benzofuranyl, benzothiophenyl, carbazolyl, benzoxazolyl,pyrimidinyl, benzimidazolyl, quinoxalinyl, benzothiazolyl,naphthyridinyl, isoxazolyl, isothiazolyl, purinyl, quinazolinyl,pyrazinyl, 1-oxidopyridyl, pyridazinyl, triazinyl, tetrazinyl,oxadiazolyl, thiadiazolyl, and so on.

The terms “arylene” and “heteroarylene” are the divalent forms of the“aryl” and “heteroaryl” groups defined above. The terms “arylenyl” and“heteroarylenyl” are used when “arylene” and “heteroarylene”,respectively, are substituted. For example, an alkylarylenyl groupcomprises an arylene moiety to which an alkyl group is attached.

The term “fused aryl ring” includes fused carbocyclic aromatic rings orring systems. Examples of fused aryl rings include benzo, naphtho,fluoreno, and indeno.

The term “annulene” refers to aryl groups that are completely conjugatedmonocyclic hydrocarbons. Examples of annulenes include cyclobutadiene,benzene, and cyclooctatetraene. Annulenes present in an aryl group willtypically have one or more hydrogen atoms substituted with other atomssuch as carbon.

When a group is present more than once in any formula or schemedescribed herein, each group (or substituent) is independently selected,whether explicitly stated or not. For example, for the formula —C(O)NR₂each of the two R groups is independently selected.

As a means of simplifying the discussion and the recitation of certainterminology used throughout this application, the terms “group” and“moiety” are used to differentiate between chemical species that allowfor substitution or that may be substituted and those that, in theparticular embodiment of the invention, do not so allow for substitutionor may not be so substituted. Thus, when the term “group” is used todescribe a chemical substituent, the described chemical materialincludes the unsubstituted group and that group with nonperoxidic O, N,S, Si, or F atoms, for example, in the chain as well as carbonyl groupsor other conventional substituents. Where the term “moiety” is used todescribe a chemical compound or substituent, only an unsubstitutedchemical material is intended to be included. For example, the phrase“alkyl group” is intended to include not only pure open chain saturatedhydrocarbon alkyl substituents, such as methyl, ethyl, propyl,tert-butyl, and the like, but also alkyl substituents bearing furthersubstituents known in the art, such as hydroxy, alkoxy, alkylsulfonyl,halogen atoms, cyano, nitro, amino, carboxyl, etc. Thus, “alkyl group”includes ether groups, haloalkyls, nitroalkyls, carboxyalkyls,hydroxyalkyls, sulfoalkyls, etc. On the other hand, the phrase “alkylmoiety” is limited to the inclusion of only pure open chain saturatedhydrocarbon alkyl substituents, such as methyl, ethyl, propyl,tert-butyl, and the like.

The invention is inclusive of the compounds described herein (includingintermediates) in any of their pharmaceutically acceptable forms,including isomers (e.g., diastereomers and enantiomers), tautomers,salts, solvates, polymorphs, prodrugs, and the like. In particular, if acompound is optically active, the invention specifically includes eachof the compound's enantiomers as well as racemic mixtures of theenantiomers. It should be understood that the term “compound” includesany or all of such forms, whether explicitly stated or not (although attimes, “salts” are explicitly stated).

“Pharmaceutically acceptable” as used herein means that the compound orcomposition or carrier is suitable for administration to a subject toachieve the treatments described herein, without unduly deleterious sideeffects in light of the necessity of the treatment.

II. The Invention

In certain aspects, the invention is directed to radiolabeled cromolynanalogs for medical imaging of inflammatory sites such asatherosclerotic plaques in the heart, brain, or carotid artery of asubject. In other aspects, the present compounds, in radiolabeled orunlabeled form, are treatment agents for various disease conditionsincluding, e.g., atherosclerotic plaques and Alzheimer's Disease.

Disodium cromoglicate, or sometimes called cromolyn, is ananti-inflammatory medication. Cromolyn is understood to be a mast cellstabilizer and apparently works by preventing the release of mediatorssuch as the vasoactive and proarrhythmogenic chemical histamine andcytokines from mast cells thus stabilizing inflammatory cells.Prevention of mediator release is thought to result from indirectblockade of the entry of calcium ions into the membrane of sensitizedmast cells. Cromolyn has also been shown to inhibit the movement ofother inflammatory cells such as neutrophils, eosinophils, andmonocytes. The present inventors describe herein the manufacture and useof new analogs and new radiolabeled analogs of cromolyn for use aspotential agents for treatment, imaging and as biomarkers for followingprogression, treatment efficacy and prevention of atherosclerosis andβ-amyloid plaque formation. In certain embodiments, cromolyn analogs areradiolabeld with nuclides that allow PET and MRI imaging. The inventionfurther provides methods for the preparation and use of the compoundsfor targeting and treating active infection and other inflammatoryprocesses, such as atherosclerosis or, alternatively, Alzheimer'sDisease.

As can be appreciated, the compounds of the present invention may beused for several purposes. For instance, the described compounds are apotential research tool for animal studies; a diagnosis agent forclinicians; a biomarker for biology studies; a potential class of drugsto treat atherosclerosis or Alzheimer's Disease; a MRI imaging probe foratherosclerosis or Alzheimer's (e.g., a compound containing at least onefluorine atom which is an ¹⁹F isotope); and a PET probe foratherosclerosis or Alzheimer's diagnosis (e.g., a compound containing atleast one fluorine atom which is an ¹⁸F isotope or, alternatively, atleast one carbon atom which is a ¹³C isotope).

Cromolyn derivatives are expected to be beneficial for use in theimaging methods of the invention. As used herein, the term “cromolynderivative” is used interchangeably with the term “cromolyn analog” and“cromolyn analogue” (alternative spelling).

Cromolyn derivatives that exhibit improved imaging qualities arepreferred. Cromolyn derivatives of the invention are generallyencompassed by compounds having the formula:

or esters or salts of (I) or (II);

wherein: X is OH, C₁-C₆ alkoxyl, ¹⁸F, or ¹⁹F; Y and Z are independentlyselected from a C₁-C₆ alkyl, C₁-C₆ alkoxyl, halogen, un-substituted orC₁-C₆ substituted amine, ¹⁸F, ¹⁹F, or H; and n is 1, 2, or 3; andwherein for structure (I), if n are both 1 and Y and Z are both H, X isnot OH.

In certain embodiments, X is ¹⁸F or ¹⁹F and, more preferably, Y and Zare hydrogen. A particularly preferred compound has the structure:

or is a salt or ester thereof.

In another embodiment, at least one of Y and Z is ¹⁸F or ¹⁹F and, morepreferably, X is OH. Particularly preferred compounds have thestructures:

or corresponding esters or salts thereof.

In an alternative embodiment, the compound lacks a radiolabel and,preferably, X is OH and Y and Z are hydrogen, except that in such anembodiment comprising structure (I) wherein X is OH and Y and Z arehydrogen, both n cannot be 1.

Preferred compounds of the invention, particularly for imaging purposes,localize to atherosclerotic plaques in the heart, brain and/or carotidartery of a subject.

A preferred dosage range of the present compounds for administration toanimals, including humans, is from about 0.001 mg/kg to about 500 mg/kg.Specifically, for PET and MRI imaging, the preferred dosage range isfrom about 0.1 mg/kg to about 500 mg/kg. Based on these parameters, theartisan may perform no more than routine experimentation to optimize thedosage for a particular application.

Compounds lacking radiolabel are, of course, useful for the treatmentmethods claimed and disclosed herein. Specific methods to synthesizeexemplary compounds according to the invention are set forth below inthe Examples section. In general, the inventors utilize novel syntheticradiofluorination approaches to provide the present compounds. Schemes Iand II shown below illustrate preferred embodiments of the manufacturingprocesses.

In certain embodiments directed to formulations and medicaments fordisease treatment including, e.g., atherosclerosis or Alzheimer's, theinventive compounds may be provided as pharmaceutically acceptablesalts. Other salts may, however, be useful in the preparation of thecompounds according to the invention or of their pharmaceuticallyacceptable salts. Suitable pharmaceutically acceptable salts of thecompounds of this invention include acid addition salts which may, forexample, be formed by mixing a solution of the compound according to theinvention with a solution of a pharmaceutically acceptable acid such ashydrochloric acid, sulphuric acid, methanesulphonic acid, fumaric acid,maleic acid, succinic acid, acetic acid, benzoic acid, oxalic acid,citric acid, tartaric acid, carbonic acid or phosphoric acid.Furthermore, where the compounds of the invention carry an acidicmoiety, suitable pharmaceutically acceptable salts thereof may includealkali metal salts, e.g. sodium or potassium salts, alkaline earth metalsalts, e.g. calcium or magnesium salts; and salts formed with suitableorganic ligands, e.g. quaternary ammonium salts.

The inventive compounds further encompass esters of the describedcompounds, wherein the acidic hydrogen on one or more of the acidicmoieties is substituted by an alkyl group.

Where the compounds according to the invention have at least oneasymmetric center, they may accordingly exist as enantiomers. Where thecompounds according to the invention possess two or more asymmetriccenters, they may additionally exist as diastereoisomers. It is to beunderstood that all such isomers and mixtures thereof in any proportionare encompassed within the scope of the present invention.

The invention also provides pharmaceutical compositions comprising oneor more compounds of this invention in association with apharmaceutically acceptable carrier. Preferably these compositions arein unit dosage forms such as tablets, pills, capsules, powders,granules, sterile parenteral solutions or suspensions, metered aerosolor liquid sprays, drops, ampoules, auto-injector devices orsuppositories; for oral, parenteral, intranasal, sublingual or rectaladministration, or for administration by inhalation or insufflation. Itis also envisioned that the compounds of the present invention may beincorporated into transdermal patches designed to deliver theappropriate amount of the drug in a continuous fashion.

For preparing solid compositions such as tablets, the principal activeingredient is mixed with a pharmaceutically acceptable carrier, e.g.conventional tableting ingredients such as corn starch, lactose,sucrose, sorbitol, talc, stearic acid, magnesium stearate, dicalciumphosphate or gums, and other pharmaceutical diluents, e.g. water, toform a solid preformulation composition containing a homogeneous mixturefor a compound of the present invention, or a pharmaceuticallyacceptable salt thereof. When referring to these preformulationcompositions as homogeneous, it is meant that the active ingredient isdispersed evenly throughout the composition so that the composition maybe easily subdivided into equally effective unit dosage forms such astablets, pills and capsules. This solid pre-formulation composition isthen subdivided into unit dosage forms of the type described abovecontaining from 0.1 to about 500 mg of the active ingredient of thepresent invention. Typical unit dosage forms contain from 1 to 100 mg,for example, 1, 2, 5, 10, 25, 50 or 100 mg, of the active ingredient.The tablets or pills of the novel composition can be coated or otherwisecompounded to provide a dosage affording the advantage of prolongedaction. For example, the tablet or pill can comprise an inner dosage andan outer dosage component, the latter being in the form of an envelopeover the former. The two components can be separated by an enteric layerwhich, serves to resist disintegration in the stomach and permits theinner component to pass intact into the duodenum or to be delayed inrelease. A variety of materials can be used for such enteric layers orcoatings, such materials including a number of polymeric acids andmixtures of polymeric acids with such materials as shellac, cetylalcohol and cellulose acetate.

The liquid forms in which the novel compositions of the presentinvention may be incorporated for administration orally or by injectioninclude aqueous solutions, suitably flavored syrups, aqueous or oilsuspensions, and flavored emulsions with edible oils such as cottonseedoil, sesame oil, coconut oil or peanut oil, as well as elixirs andsimilar pharmaceutical vehicles. Suitable dispersing or suspendingagents for aqueous suspensions include synthetic and natural gums suchas tragacanth, acacia, alginate, dextran, sodium carboxymethylcellulose,methylcellulose, polyvinylpyrrolidone or gelatin.

The compounds of the present invention are particularly useful whenformulated in the form of a pharmaceutical injectable dosage, includinga compound described and claimed herein in combination with aninjectable carrier system. As used herein, injectable and infusiondosage forms (i.e., parenteral dosage forms) include, but are notlimited to, liposomal injectables or a lipid bilayer vesicle havingphospholipids that encapsulate an active drug substance. Injectionincludes a sterile preparation intended for parenteral use.

Five distinct classes of injections exist as defined by the USP:emulsions, lipids, powders, solutions and suspensions. Emulsioninjection includes an emulsion comprising a sterile, pyrogen-freepreparation intended to be administered parenterally. Lipid complex andpowder for solution injection are sterile preparations intended forreconstitution to form a solution for parenteral use. Powder forsuspension injection is a sterile preparation intended forreconstitution to form a suspension for parenteral use. Powderlyophilized for liposomal suspension injection is a sterile freeze driedpreparation intended for reconstitution for parenteral use that isformulated in a manner allowing incorporation of liposomes, such as alipid bilayer vesicle having phospholipids used to encapsulate an activedrug substance within a lipid bilayer or in an aqueous space, wherebythe formulation may be formed upon reconstitution. Powder lyophilizedfor solution injection is a dosage form intended for the solutionprepared by lyophilization (“freeze drying”), whereby the processinvolves removing water from products in a frozen state at extremely lowpressures, and whereby subsequent addition of liquid creates a solutionthat conforms in all respects to the requirements for injections. Powderlyophilized for suspension injection is a liquid preparation intendedfor parenteral use that contains solids suspended in a suitable fluidmedium, and it conforms in all respects to the requirements for SterileSuspensions, whereby the medicinal agents intended for the suspensionare prepared by lyophilization. Solution injection involves a liquidpreparation containing one or more drug substances dissolved in asuitable solvent or mixture of mutually miscible solvents that issuitable for injection. Solution concentrate injection involves asterile preparation for parenteral use that, upon addition of suitablesolvents, yields a solution conforming in all respects to therequirements for injections. Suspension injection involves a liquidpreparation (suitable for injection) containing solid particlesdispersed throughout a liquid phase, whereby the particles areinsoluble, and whereby an oil phase is dispersed throughout an aqueousphase or vice-versa. Suspension liposomal injection is a liquidpreparation (suitable for injection) having an oil phase dispersedthroughout an aqueous phase in such a manner that liposomes (a lipidbilayer vesicle usually containing phospholipids used to encapsulate anactive drug substance either within a lipid bilayer or in an aqueousspace) are formed. Suspension sonicated injection is a liquidpreparation (suitable for injection) containing solid particlesdispersed throughout a liquid phase, whereby the particles areinsoluble. In addition, the product may be sonicated as a gas is bubbledthrough the suspension resulting in the formation of microspheres by thesolid particles.

The parenteral carrier system includes one or more pharmaceuticallysuitable excipients, such as solvents and co-solvents, solubilizingagents, wetting agents, suspending agents, thickening agents,emulsifying agents, chelating agents, buffers, pH adjusters,antioxidants, reducing agents, antimicrobial preservatives, bulkingagents, protectants, tonicity adjusters, and special additives.

The compounds according to the present invention are anticipated to actas treatment agents for inflammation, particularly atheroscleroticplaques, as can be demonstrated by standard protocols commonly known inthe field. Accordingly, another aspect of the invention provides amethod for treating atherosclerotic plaque in a subject, comprisingadministering to a subject an effective dosage of a compound accordingto the present invention, whereby the atherosclerotic plaque is treatedin the subject. In the treatment of atherosclerotic plaque, suitabledosage level (i.e, an effective amount) is from about 0.001 mg/kg toabout 500 mg/kg per day, preferably about 1 mg/kg per day. The compoundsmay be administered on a regimen of 1 to 4 times per day, or on acontinuous basis.

The compounds according to the present invention are anticipated to actas treatment agents for Alzheimer's Disease, as can be demonstrated bystandard protocols commonly known in the field. Accordingly, anotheraspect of the invention provides a method for treating Alzheimer'sDisease in a subject, comprising administering to a subject an effectivedosage of a compound of the invention, whereby Alzheimer's Disease istreated in the subject. In the treatment of Alzheimer's Disease,suitable dosage level (i.e, an effective amount) is from about 0.001mg/kg to about 500 mg/kg per day, preferably about 1 mg/kg per day. Thecompounds may be administered on a regimen of 1 to 4 times per day, oron a continuous basis.

The following examples are, of course, offered for illustrative purposesonly, and are not intended to limit the scope of the present inventionin any way. Indeed, various modifications of the invention in additionto those shown and described herein will become apparent to thoseskilled in the art from the foregoing description and the followingexamples and fall within the scope of the appended claims.

III. Examples

Example 1

Synthesis of F-18 Labeled Cromolyn

Radiofluorination.

5,5′-(2-[18F]fluoropropane-1,3-diyl)bis(oxy)bis(4-oxo-4H-chromene-2-carboxylicacid)

A Wheaton 5-mL reaction vial containing 50 mCi of fluorine-18 in 1 mL of¹⁸O-enriched water, Kryptofix-2.2.2. (6 mg), and potassium carbonate (2mg) was heated at 120° C. and solvent was evaporated with the aid ofnitrogen gas. The K¹⁸F/Kryptofix complex was dried three times at 120°C. by the addition of 1 mL of acetonitrile followed by evaporation ofthe solvent using a nitrogen flow. A solution of1,3-bis[tolylsulfonyl)oxy]-2-[(trifluoromethyl)sulfonyl]oxy-propane (4mg) in acetonitrile was added to the vial and fluorination was performedat 80° C. for 10 min. The resultant 2-[¹⁸F]fluoropropane 1,3-ditosylatesolution (90% r×n, radioTLC) was passed through a silica gel SepPakusing methylene chloride into a vial containing K₂CO₃ (10 mg) and ethyl5-hydroxy-4-oxo-4H-chromene-2-carboxylate (10 mg). After solventremoval, N-methyl-2-pyrrolidone (NMP) was added and the mixture washeated for 20 min at 140° C. Once cooled, 1M NaOH (100 uL) was added andthe mixture was heated for 10 min at 80° C. The mixture was diluted with1M HCl (3 mL) and passed through a C-18 SepPak. Polar materials wereeluted with 1M HCl and F-18 cromolyn with 20:80 acetonitrile/PBS (1 mL).F-18 cromolyn was purified by HPLC (Phenomenex Luna C18, 250×10 mm,gradient: 0 to 40% acetonitrile in 20 mM phosphate buffer, pH 6.5).Solvent was evaporated the activity (5 mCi, 20% BOB) was dissolved insaline and filtered (0.22μ Millex-GV). Synthesis was complete within 2hr and chemical purity was greater than 95%.

Example 2

Synthesis of Precursors

2-Carbethoxy-5-hydroxy-γ-chromone

A mixture of 2,6-dihydroxyacetophenone (1.0 g, 6.6 mmol) and ethyloxalate (0.15 g, 6.6 mmol) in ether (10 mL) was added to a solution ofsodium ethoxide (0.4 g Na, 20 mmol) in ethanol (15 mL). The mixture wasstirred at 25° C. for 30 min, heated at reflux for 1.5 hr, cooled andfiltered. The precipitated sodium salt was washed with ether and dried.It was then dissolved in water and acidified with 10% HCl to form asticky solid. The solid was refluxed in ethanol (20 mL) with a catalyticamount of 36% HCL for 1 hr. The mixture was poured into 50 mL of waterand extracted twice with methylene chloride (50 mL). The extracts werecombined and dried. After solvent removal, the crude material waschromatographed on silica gel (ethyl acetate/hexane 20:80) to yield 0.57g (40%) of a yellow product; mp 146-148° C. (Lit. 148° C.); ¹H NMR(CDCl₃), d 1.42 (t, 3H, J=7.14 Hz, CH3), 4.47 (q, 2H, J=7.14 Hz), 6.82(d, 2H, J=8.24 Hz, Aro-H), 7.02 (d, 2H, J=4.0 Hz, Aro-H), 7.02 (s, 1H,vinyl-H), 7.58 (t, 1H, J=8.24 Hz, Aro-H), 12.1 (s, 1H, phenol-H).

1,3-Bis(4-methylbenzenesulfonate)propanetriol

A solution of glycerol (11 g, 120 mmol) in methylene chloride (80 mL),DMAP (30 mg) and pyridine (20 mL) was treated at 0-5° C. withp-toluenesulfonyl chloride (54.6 g, 239 mmol) over a period of 30 min.The mixture was stirred at 25° C. for 16 hr, diluted with water (100 mL)and layers separated. The methylene chloride layer was washed with 1NHCl until the wash solution was acidic and then dried (sodium sulfate).After solvent removal, the crude material was chromatographed on silicagel (methanol/methylene chloride 0:100 to 5:95) to yield 14.5 g (30%) ofan oil; ¹H NMR (CDCl₃), δ 2.5 (s, 6H, CH3), 4.25 (m, 4H, CH2), 5.09 (m,1H, CH), 7.4 (d, 4H, J=8.1 Hz, Aro-H), 7.78 (d, 4H, J=8.4 Hz, Aro-H).

1,3-Bis(4-methylbenzenesulfonate)-2-trifluoromethylsulfonatepropanetriol

A mixture of 1,3-bis(4-methylbenzenesulfonate) propanetriol 100 mg (0.25mmol) in methylene chloride (20 mL) and pyridine (1 mL) at 0-5° C. wastreated with trifluoromethanesulfonic anhydride (141 mg, 0.50 mmol). Themixture was stirred at 0-5° C. for 1 hr and then allowed to warm to 25°C. and stirred for 4 hr. The mixture was diluted with water (30 mL) andlayers separated. The methylene chloride layer was washed with 1N HCluntil the wash solution was acidic and then dried (sodium sulfate).After solvent removal, the crude material was chromatographed on silicagel (methylene chloride) to yield 66 mg (50%) of a solid; mp 145-147°C.; ¹H NMR (CDCl₃), δ 2.5 (s, 6H, CH3), 4.25 (d, 4H, J=4.6 Hz, CH2, 5.09(m, 1H, CH), 7.4 (d, 4H, J=8.1 Hz, Aro-H), 7.78 (d, 4H, J=8.4 Hz,Aro-H).

3-Bis(4-methylbenzenesulfonate)-2-fluoropropanediol

A solution of 1,3-bis(4-methylbenzenesulfonate) propanetriol (2.7 g,6.78 mmol) in methylene chloride (20 mL) at 0-5° C. was treated withDAST (2.18 g, 13.6 mmol). The mixture was stirred at 0-5° C. for 30 thenallowed to warm to 25 and stirred for 16 hr. The mixture was poured intoa sat'd sodium bicarbonate solution (30 mL) and layers separated. Themethylene chloride layer dried (sodium sulfate). After solvent removal,the crude material was chromatographed on silica gel (methylenechloride) to yield 0.82 g (30%) of a solid; mp 99-102° C.; ¹H NMR(CDCl₃), δ 2.5 (s, 6H, CH3), 4.15 (dd, 4H, J=12.3, 4.6 Hz, CH2, 4.8 (dq,1H, J=47, 4.6, CHF), 7.45 (d, 4H, J=8.1 Hz, Aro-H), 7.75 (d, 4H, J=8.4Hz, Aro-H).

Example 3

Synthesis of Standard

5,5′-(2-fluoropropane-1,3-diyl)bis(oxy)bis(4-oxo-4H-chromene-2-carboxylicacid)

1,3-Bis(2-acetyl-3-hydroxyphenoxy)-2-fluoropropane

A mixture of 3-bis(4-methylbenzenesulfonate)-2-fluoropropanediol (1.0,2.5 mmol), 2,6-dihydroxyacetophenone (0.76 g, 5.0 mmol) and potassiumcarbonate (0.69 g) in acetonitrile (40 mL) was heated under reflux for16 hr. The mixture was filtered and the filtrate was evaporated. Thecrude material was chromatographed on silica gel (acetonitrile/methylenechloride 5:95) to yield 0.57 g (40%) of product; mp 162-165° C.; ¹H NMR(d6-DMSO), δ 2.5 (s, 6H, 2CH3), 4.38 (m, 4H, 2CH2), 5.22 (br d 1H, J=49Hz, CHF), 6.45 (m, 4H, 4Aro-H), 7.28 (t, 2H, J=4.55 Hz, 2Aro-H).

1,3-Bis(2-carboxychromon-5-yloxy)-2-fluoropropane diethyl ester

A mixture of 1,3-bis(2-acety-3-hydroxyphenoxy)-2-fluoropropane (200 mg,0.52 mmol) and ethyl oxalate (2 mL) was added to a solution of sodiumethoxide (87 mg Na) in ethanol (10 mL) and benzene (10 mL). The mixturewas heated at reflux for 16 hr, cooled and diluted with ether (50 mL).The precipitated sodium salt was filtered, washed with ether and dried.It was then dissolved in water and acidified with 10% HCl to obtain asticky solid. The solid was refluxed in ethanol (20 mL) with a catalyticamount of 36% HCL for 1 hr. The mixture was poured into 50 mL of waterand extracted twice with methylene chloride (50 mL). The extracts werecombined and dried. After solvent removal, the crude material waschromatographed on silica gel (acetonitrile/methylene chloride 10:90) toyield 0.12 g (45%) of a white product; mp 166-170° C.; ¹H NMR (CDCl₃), d1.42 (t, 6H, J=7.14 Hz, 2CH3), 4.58 (q, 4H, J=7.14 Hz 2CH2), 4.65 (m,4H, 2CH2), 5.35 (dq, 1H, J=46 Hz, J=4.4 HZ, CHF), 6.90 (s, 2H, vinyl-H),6.95 (d, 2H, J=8.24 Hz, 2Aro-H), 7.13 (d, 2H, J=8.24 Hz, 2Aro-H) 7.6 (t,2H, J=8.24 2Aro-H).

5,5′-(2-fluoropropane-1,3-diyl)bis(oxy)bis(4-oxo-4H-chromene-2-carboxylicacid)

A suspension of 1,3-bis(2-carboxychromon-5-yloxy)-2-fluoropropanediethyl ester (100 mg, 0.19 mmol) in methanol (20 mL) and 1 M sodiumhydroxide (2 mL) was heated at 80 C for 1 hr. The solution was acidifiedwith 10% HCl and volatiles were removed. A solution ofmethanol/methylene chloride (50:50) was added to the solid and themixture was filtered. Evaporation afforded 76 mg (85%) of product; ¹HNMR (d6-DMSO), δ 4.65 (m, 4H, 2CH2), 5.32 (br d, 1H, J=46 Hz, CHF), 6.80(s, 2H, 2vinyl-H), 7.2 (d, 2H, J=8.24 Hz, 2Aro-H), 7.71 (t, 2H, J=8.242Aro-H).

Example 4

Biodistribution

Biodistribution of F-18 cromolyn (Compound A) was performed in normalmice at 5, 30 and 60 min after intravenous injection into the tail vein(50 uCi per animal). At 5 min, organ activity (DPG) was: heart: 1.09%,blood: 3.3%, lung: 1.90%, liver: 7.69%, and brain: 0.15%. At 30 and 60min, washout of activity was seen in all organs. Heart uptake wasdecreased from 1.09% to 0.18%. The data is provided in Table 1 below andin bar graph format in FIG. 1.

TABLE 1 F-18 Cromolyn Tissue Distribution (% Dose/gram) in Normal MiceOrgan 5 min 30 min 60 min blood 3.31 ± 1.37 0.92 ± 0.20 0.44 ± 0.15heart 1.09 ± 0.13 0.32 ± 0.03 0.18 ± 0.07 lung 1.90 ± 1.04 0.62 ± 0.190.29 ± 0.21 liver 7.69 ± 0.41 3.11 ± 0.36 1.76 ± 0.74 brain 0.15 ± 0.37 0.04 ± 0.007  0.03 ± 0.004 Standard deviation (±)

Example 5

Aromatic Radiofluorination

Radiofluorination of cromolyn N,N,N-trimethylbenzenaminium triflate isdone in a sealed vial containing dry K¹⁸F/Kryptofix in dimethylacetamide(DMAc) for 5 min at 140° C. The resultant F-18 cromolyn solution isdiluted with water and passed through a C-18 SepPak. Polar materials areeluted with water and product eluted with methanol into a vial. Asolution of 1N sodium hydroxide is added and the vial is heated for 10min at 80° C. The mixture is acidified and F-18 cromolyn is purified byHPLC.

Alternative Route:

Example 6

Synthesis of Precursors

1-(4-Amino-2,6-dimethoxyacetophenone) [Dillon, Michael Patrick;Jahangir, Alam; Moore, Amy Geraldine; Wagner, Paul J. U.S. Pat. Appl.Publ. (2007), 49 pp]

Step 1. N-(3,5-Dimethoxyphenyl)-2,2,2-trifluoroacetamide

To 3,5-dimethoxyaniline (20 g, 131 mmol) dissolved in anhydroustetrahydrofuran (90 mL) was added 4-(dimethylamin) pyridine (1.6 g, 13.1mmol) and ethyl trifluoroacetate (47 mL, 392 mmol). After refluxing 48hours, the cooled reaction mixture was concentrated and partitionedbetween ethyl acetate (300 mL) and 2N hydrochloric acid (100 mL). Theethyl acetate layer is washed with water (100 mL), dried using anhydroussodium sulfate, and concentrated to yieldN-(3,5-dimethoxyphenyl)-2,2,2-trifluoroacetamide (31.8 g, 98%) as a paleyellow solid.

Step 2. N-(4-Acetyl-3,5-dimethoxyphenyl)-2,2,2-trifluoroacetamide

To a solution of N-(3,5-dimethoxyphenyl)-2,2,2-trifluoroacetamide (31.8g, 130 mmol) in anhydrous methylene chloride (450 mL), cooled in an icebath, is added a solution of tin (IV) chloride (29.9 mL, 260 mmoldissolved in 30 mL anhydrous methylene chloride) dropwise over 10minutes. Acetyl chloride (9.1 mL, 130 mmol) is added slowly, maintainingthe temperature of the reaction below 5° C. After stirring 3 hours atroom temperature, the reaction is cooled in an ice bath. Water (300 mL)is added, maintaining the temperature of the reaction below 25° C., andthe reaction is stirred at room temperature for 18 hours. The reactionmixture is extracted with methylene chloride, and the organic layer isseparated, washed with water, dried, filtered and evaporated underreduced pressure. The residue is purified by silica gel columnchromatography eluting with 20% to 30% hexanes/ethyl acetate to yieldN-(4-acetyl-3,5-dimethoxyphenyl)-2,2,2-trifluoroacetamide (4.8 g, 13%)as a white solid.

Step 3. 1-(4-Amino-2,6-dimethoxyacetophenone)

To N-(4-Acetyl-3,5-dimethoxyphenyl)-2,2,2-trifluoroacetamide (4.3 g,14.8 mmol) dissolved in methanol (90 mL) is added anhydrous potassiumcarbonate (4.67 g, 33.8 mmol). After refluxing for 18 hours, thereaction mixture is cooled and concentrated under reduced pressure. Theconcentrate is extracted with ethyl acetate and the organic layer waswashed with brine, dried, filtered and concentrated under reducedpressure to yield 4-amino-2,6-dimethoxyacetophenone (2.5 g, 87%) as apale yellow solid.

4-Dimethylamino-2,6-hydroxyacetophenone [Brooks P R, Wirtz C, et al. J.Org. Chem. 1999, 64:9719-21]

4-Amino-2,6-dimethoxyacetophenone and n-tetrabutylammonium iodide isstirred in methylene chloride at −78 C. A solution of boron trichloridein methylene chloride is added and the solution is then stirred at 0° C.for 1 hr. The reaction is quenched with ice-water and stirred for 30min, diluted with saturated sodium bicarbonate, and extracted withmethylene chloride. The combined extracts are dried and purified bychromatography on silica gel to provide4-dimethylamino-2,6-hydroxyacetophenone.

2-Carbethoxy-3-dimethylamino-5-hydroxy-γ-chromone ethyl ester or2-Carbethoxy-4-hydroxy-γ-chromone ethyl ester

A mixture of 4-dimethylamino-2,6-hydroxyacetophenone (or2,5-dihydroxy-acetophenone) (Sigma-Aldrich) and ethyl oxalate in etheris added to a solution of sodium ethoxide in ethanol. The mixture isstirred at 25° C. for 30 min, heated at reflux for 1.5 hr, cooled andfiltered. The precipitated sodium salt is washed with ether and dried.It is then dissolved in water and acidified with 10% HCl to form asticky solid. The solid is refluxed in ethanol (20 mL) with a catalyticamount of 36% HCL for 1 hr. The mixture is poured into 50 mL of waterand extracted twice with methylene chloride (50 mL). The extracts arecombined and dried. After solvent removal, the crude material ischromatographed on silica gel (ethyl acetate/hexane 20:80) to yield2-carbethoxy-3-dimethylamino-5-hydroxy-γ-chromone ethyl ester (or2-carbethoxy-4-hydroxy-γ-chromone ethyl ester).

A mixture of 1,3-bis[(tolylsulfonyl)oxy]-2-propanol (1 equivalent),2-carbethoxy-5-hydroxy-γ-chromone ethyl ester (or2-carbethoxy-5-hydroxy-γ-chromone ethyl ester) (1 equivalent) andpotassium carbonate in N-methyl-2-pyrrolidone (NMP) is heated for 6 hrat 140° C. Once cooled, the mixture is diluted with water and extractedwith methylene chloride. Extracts are combined and dried. After solventremoval, the crude material is chromatographed on silica gel to yieldproduct.

A mixture of 2-carbethoxy-3-dimethylamino-5-hydroxy-γ-chromone ethylester (1 equivalent), the appropriate 2-propanol tosylate above andpotassium carbonate in N-methyl-2-pyrrolidone is heated for 6 hr at 140°C. Once cooled the mixture is diluted with water and extracted withmethylene chloride. Extracts are combined and dried. After solventremoval, the crude material is chromatographed on silica gel to yieldproduct.

Example 7

Acetylation of Cromolyn Derivatives

A solution of the cromolyn derivative in methylene chloride and pyridineis treated with acetic anhydride at 0° C. and then allowed to warm to25° C. where it is stirred for 4 hr. The mixture is washed with 10%sodium bicarbonate and dried. The solvents are removed by vacuum and thecrude solid is purified by chromatography.

Example 8

Preparation of Trimethyl Amomonium Triflate Salts

A solution of the acetylated cromolyn derivative in methylene chlorideis treated with trifluoromethylsulfonic anhydride at 25° C. for 4 hr.The resultant salt is filtered and washed with methylene chloride.

Example 9

Cromolyn derivative (Compound A) inhibits polymerization of Alzheimer'sDisease oligomers.

One of the common goals in treating Alzheimer's Disease is to eliminateor reduce the AB oligomers that are the neuron toxins. Achieving thisgoal slows down Alzheimer's manifestation. One way to demonstrate theefficacy of a drug to treat Alzheimer's is to test for the inhibition ofthe polymerization of the AB oligomers.

The study described in this example was based on the assay described byFindeis, et al. “Modified-peptide inhibitors of amyloid beta-peptidepolymerization.” Biochemistry 1999, 38 (21), 6791-800.

AB Peptide: 50 μM of HCl salt or Test compound (Compound A): 50 μM

Buffer: 10 mM sodium phosphate, 100 mM NaCl, pH 7.4

Readout polymerization at: OD 405 nm

The results showed that amyloid beta-peptide polymerization in thepresence of cromolyn derivative (Compound A) is 2.5 times slower thanamyloid beta-peptide polymerization in the presence of a controlvehicle.

TABLE 2 Experimental results Compound Time Relative increase Vehicle (noAdd) 7.97 (1.0) TS734 (Compound A) 19.9 2.5 *Time is elapsed time to 50%of maximum signal *Relative increase is time(sample)/time(vehicle)

The data above indicate that exemplary Compound A exhibits appreciablebrain uptake and clearance and, in terms of efficacy, inhibits ABpeptide polymerization. Compound A and related chemical entities aretherefore useful for treatment of Alzheimer's Disease in human subjects.

Example 10 Synthesis of5,5′-(2-[18F]fluorotrimethylenedioxy)bis(4-oxochromene-2-carboxylicacid) Sodium Salt

5,5′-(2-Hydroxytrimethylenedioxy)bis(4-oxochromene-2-carboxylic acid)diethyl ester. A suspension of cromolyn sodium salt 1 (161 mg, 0.31mmol) in ethanol (25 mL) and cone. HCl (1 mL) was heated in a sealedflask for 28 h at 95-100° C. The suspension dissolved to give a clearcolorless solution. Solvent was evaporated and the crude oil waschromatographed on silica gel using 100% ethyl acetate to yield thediethyl ester 2 (132 mg, 80%): TLC Rf=0.44 (100% ethyl acetate); 1HNMR(CDCb, 300 MHz) δ 1.42 (t, 3H, J=7.1 Hz, CH3), 2.73 (br s, 1H, OH), 4.44(q, 4H, J=7.1 Hz, 20CH2CH3), 4.32-4.59 (m, 5H, CHOH, 20CH2), 6.93-6.99(m, 4H, 2 vinyl H, 2 aromatic H), 7.16 (d, 2H, J=8.4 Hz, aromatic H),7.59 (t, 211, J=8.2 Hz, aromatic H)

1,3-bis(2-(ethoxycarbonyl)-4-oxo-4H-chromen-5-yloxy)propan-2-ylmethanesulfonate. A solution of the alcohol 2 (107 mg, 0.20 mmol) andtriethylamine (41 mg, 0.41 mmol) in dichlormethane (25 mL) cooled to 0°C. was treated with methanesulfonyl chloride (34 mg, 0.30 mmol). Afterstirring for 2 h at 0° C., methylene chloride (100 mL) was added and themixture was washed with satd. NaHC03 (2×30 mL) and brine (50 mL), driedover MgS04, and concentrated. The residue was purified by flash columnchromatography (80% ethyl acetate in hexane) to give the product 3 (102mg, 84%): TLC R.=0.54 (ethyl acetate); 1H NMR (CDCI3, 300 MHz 8 1.39 (t,3H, J=7.1 Hz, CH3), 3.35 (s, 3H, CH3S02), 4.41 (q, 4H, J=7.2 Hz,20CH2CH3), 4.55-4.66 (m, 4H, 20CH2), 5.40 (quintet, 1H, J=5.0, CHOMs),6.89 (s, 2H, vinyl H), 6.98 (d, 2H, J=8.4 Hz, aromatic H), 7.16 (d, 2H,J=8.8 Hz, aromatic H), 7.61 (t, 2H, J=8.2 Hz, aromatic H); 13C NMR(CDCb, 75 MHz, Ib=1.0 Hz) δ: 14.3, 38.6, 63.1, 68.7, 77.9, 108.7, 111.8,115.6, 116.4, 135.2, 150.7, 158.0, 160.7, 177.7.

5,5′-(2-[18F]Fluorotrimethylenedioxy)bis(4-oxochromene-2-carboxylicacid) sodium salt. A Wheaton 5-mL reaction vial containing fluorine-18(100 mCi) inl mL 180-enriched water, and ammonium hydroxide (100 ul) washeated at 120° C. and water was evaporated with the aid of a nitrogengas flow. The contents were dried by the addition of 1 mL ofacetonitrile followed by evaporation of solvent using a nitrogen flow.This process is repeated three times. A solution of 3 mg of mesylate 3in 0.1 mL of acetonitrile was added to the sealed vial and fluorinationwas performed at 170° C. for 10 min. Onced cooled to room temperature,the reaction mixture was passed through a silica gel Sep-Pak usingmethylene chloride (3 mL) and the solvent was removed using a nitrogenflow. A mixture of 0.5 mL 1 M lithium hydroxide and 1 mL methanol wasadded to the reaction vial and the vial heated at 80° C. for 20 min.Solvent was removed and15,5′-(2-[18F]fluorotrimethylenedioxy)bis(4-oxochromene-2-carboxylicacid) sodium salt was purified on a C18 Sep-Pak using PBS, ph 7, and thesolution was filtered (MillexGV 0.22 um). Radiochemical yield ranged for5 to 20% EOB.

Example 11 Synthetic Route for Asymmetric Cromolyn

This example illustrates the inventors' general route for synthesis ofasymmetric cromolyn derivatives.

Other embodiments and uses of the invention will be apparent to thoseskilled in the art from consideration from the specification andpractice of the invention disclosed herein. All references cited hereinfor any reason, including all journal citations and U.S./foreign patentsand patent applications, are specifically and entirely incorporatedherein by reference. It is understood that the invention is not confinedto the specific reagents, formulations, reaction conditions, etc.,herein illustrated and described, but embraces such modified formsthereof as come within the scope of the following claims.

REFERENCES

-   1. American Heart Association: Heart Disease and Stroke Statistics    2004.-   2. Libby P. Inflammation in Atherosclerosis. Nature. 2002;    420:868-74.-   3. Fernex M. The mast-cell system, its relationship to    atherosclerosis, fibrosis and eosinophils. Basel, New York, Karger,    1968.-   4. Mor A, and Mekori Y A. Mast Cells and Atherosclerosis. Israel    Medical Association Journal; 2001; 3:216-221.-   5. Kelly J L, Chi O S, Abou-Auda W, Smith J K, Krishnaswamy G. The    molecular role of mast cells in atherosclerotic cardiovascular    disease. Mol Med. Today. 2000; 6:304-08.-   6. Sun J, Sukhova G K, Wolters P J, Yang M, Kitamoto S, Libby P,    MacFarlane L A, Mallen-St Clair J, Shi G P. Mast cells promote    atherosclerosis by releasing proinflammatory cytokines. Nature    Medicine 2007; 13, 719-724.-   7. Huang M, Pang X, Letourneau R, Boucher W, Theoharides T C. Acute    stress induces cardiac mast cell activation and histamine release,    effects that are increased in Apolipoprotein E knockout mice.    Cardiovascular Research 2002 55(1):150-160.-   8. Gilman A G, Rail T W, Nies A S, et al., editors. Goodman and    Gilman's the pharmacological basis of therapeutics. 8th ed. New    York: Pergamon Press; 1990. p. 630-1; Murphy S. Cromolyn sodium:    basic mechanisms and clinical usage. Pediatr Asthma Allergy    Immuno/1988; 2: 237-54.-   9. Bot I, de Jager S C, Zernecke A, Lindstedt K A, van Berkel T J,    Weber C, Biessen E A. Perivascular mast cells promote atherogenesis    and induce plaque destabilization in apolipoprotein E-deficient    mice. Circulation. 2007; 115: 2516-2525.-   10. Huang M, Pang X, Karalis K, Theoharides T C. Stress-induced    interleukin-6 release in mice is mast cell-dependent and more    pronounced in Apolipoprotein E knockout mice. Cardiovascular    Research 2003 59(1):241-249.-   11. Findeis et al., “Modified-Peptide Inhibitors of Amyloid    β-Peptide Polymerization,” Biochemistry 1999, 38, 6791-6800-   12. Findeis and Molineaux, “Design and Testing of Inhibitors of    Fibril Formation,” Methods in Enzymology, 1999, 309, 476-488

What is claimed is:
 1. A compound having the formula:

or a salt or ester of (I) or (II); wherein: X is ¹⁸F, or ¹⁹F; Y and Zare independently selected from a C₁-C₆ alkyl, C₁-C₆ alkoxyl, halogen,un-substituted or C1-C6 substituted amine, ¹⁸F, ¹⁹F, or H; and n is 1,2, or
 3. 2. The compound according to claim 1, wherein Y and Z are H. 3.The compound according to claim 2, wherein said compound has thestructure:

or a salt or ester thereof.
 4. The compound according to claim 1,wherein at least one of Y and Z is ¹⁸F or ¹⁹F.
 5. A pharmaceuticalcomposition, comprising the compound of claim 1 and a pharmaceuticallyacceptable carrier.
 6. A method of treating atherosclerotic plaque in asubject, comprising administering to a subject an effective dosage of acompound according to claim 1, whereby the atherosclerotic plaque istreated in said subject.
 7. A method of treating Alzheimer's Disease ina subject, comprising administering to a subject an effective dosage ofa compound according to claim 1, whereby Alzheimer's Disease is treatedin said subject.
 8. A compound according to claim 1 for use in in vivoimaging of a subject.
 9. A compound according to claim 1 for use intreating atherosclerotic plaque or Alzheimer's disease in a subject.